Improvement in varnishes for coating photographic negatives



4 aura fitter new (we JOHAN WOLFGANG MORGENEIER, OFSHEBOYGAN,-WISCONSIN.

Letters Patent No. 109,833, dated December 6, 1870.

IMPROVEMENT IN VARNISHES FOR COATING PHOTOGRAPHIC NEGATIVES.

' The Schedule referred to in these Letters Patent and making part ofthe lame.

T o whom it may concern:

Be it known that I, JOHAN WOLFGANG Monennegatives to facilitateretouching either with leadpencils or water-colors, by coating the samewith a varnish composed of theingredient-s, and in or about theproportions hereinafter set forth.

For this purpose 1 compound two solutions, the

I following being the formula for their preparation:

- No. l. Dissolve in two and two-third ounces absolute alcohol,ninety-five per cent. by fiuid measure, one-half ounce gum sandarak,(picked,) by weight; one and one-half dram Venetian turpentine, byweight; one. dram oil of lavender, by weight.

No. 2. Dissolve in five and one-half drams absolute alcohol, ninety-fiveper cent.,-fiuid measure, one and one-third drain concentrated sulphuricether, fluid measure; one and one-third dram gum camphor, by

f weight; two and two-third drams pure rain-water,

fluid measure.

- Mix the two solutions together by thoroughly shaking them; let thevarnish thus made stand a day or two, when it is ready for use, when itmay be applied to a contact plate in the same manner as collodion in'the ordinary wet-process. After the negative is developed, intensified,fixed with cyanide of potassium, washed and dried, the plate is coatedwith the varnish, drained, and set to dry in a cool current of air. Whendry it will present a--hard,-dead, and Iusterless surface, resemblingground glass, which can be retonched and worked with great easeandcelerity with any grade of pencil from one to five, (Faber,) or withwater-colors, byst-ippling or otherwise.

In varnishing solar negatives, let 'the plate drain well, and lie withthe varnish side upward, von a per feet lever, to avoid streaks. Thefilmon sol'ar'negatives does not lengthen the time required for printing.

7 The photographer should observe the following rules I to produce thebest results: 7 Use no other intensifier than pyrogallic acid, and

do-not intensify too much, as the negative is intensified to a certainextent by the varnish.

In extremely hot, cold,or damp weath er the varnished plate, when dry,may appear spotted; by varnishing it again the spots will disappear.

If necessary to use the plate immediately, allow the varnish to set afew rninutes'after drawing the plate,

and then dry over a'moderate heat but, in'all cases, the plate must becool when the varnish is applied.

If the negative hasbeen touched too intensely, the

work can be removed without injury to the film by using a soft, roundcamel-hair brush dipped in water.

This varnish will not crack or peel in the hottest weather, nor will thepaper stick to the plate.

\Vhat I claim as my invention, and desire to secure by Letters Patent,isv The varnish for coating photographic negatives, composed of theiugredients, and in or about the proportions herein set forth.

1 J OHAN WOLFGANG MORGENEIER.

Witnesses:

ANTON HAMMER, J. ULEIS Rorn'r, M. STEWART.-

